1. Field of the Invention
The present invention concerns a composition for inducing and stimulating hair growth and/or reducing its loss containing, in combination, at least one pyrimidine derivative and at least one alkylpolyglycoside surfactant.
Man has about 100 000 to 150 000 hairs on the head and a daily loss of 50 to 100 hairs is normal. Maintaining a head of hair is essentially dependent on a pilary cycle during which the hair is formed, grows and then falls out before being replaced by a new hair growing from the same follicle.
Three phases occur during the pilary cycle: the anagenous, catagenous and telogenous phases.
During the first or anagenous phase the hair undergoes a period of active growth associated with intense metabolic activity in the root.
The second or catagenous phase is transitory and characterised by a slowing down of metabolic activity. During this phase the hair undergoes involution, the follicle atrophies and its dermal implantation appears higher and higher.
The final or telogenous phase corresponds to a rest period for the follicle and the hair finally falls out, pushed out by a new hair in its anagenous phase.
This permanent renewal process undergoes a natural evolution during ageing whereby the hair becomes finer and the cycles shorter.
Alopecia occurs when this physical renewal process is accelerated or perturbed, ie growth phases are shortened, passage of hair into the telogenous phase speeds up and hair falls out more frequently. Successive growth cycles result in finer and finer, shorter and shorter hair, gradually resulting in unpigmented down. This phenomenon may result in baldness.
Several factors, eg alimentary, endocrinal or nervous factors, may affect the pilary cycle and result in more or less pronounced alopecia.
Variations in the different phases may be determined using a trichogram, in particular a phototrichogram.
For several years, the cosmetics and pharmaceuticals industries have sought compositions which will cure or reduce alopecia, particularly ones which will induce or stimulate hair growth or reduce hair loss.
2. Description of the Prior Art
In this respect compositions such as 6-amino -1,2-dihydro-1-hydroxy-2-imino-4-piperidinopyrimidine and its derivatives have already been used. Such compositions are described in U.S. Pat. No. 4,139,619 in particular.
In order to improve the efficacy of compositions containing pyrimidic derivatives, a composition has been sought which is tolerated well and contains pyrimidine derivative(s) which can remain in contact with the scalp over a prolonged period without being rinsed away, to encourage penetration of the active substance into the horny layer.
In this regard the applicant has discovered that by using an alkylpolyglycoside in combination with the pyrimidine derivatives it is possible to improve the efficacy of the composition in inducing and stimulating hair growth and reducing hair loss.
Combinations of the two compounds can produce compositions which are more efficaceous than those previously known and which can be used in a manner which is particularly easy and appropriate for application of active ingredients.
Use of an alkylpolyglycoside in combination with the pyrimidine derivative also allows remarkably easy elimination of the composition simply by rinsing.
The applicant has also established that the composition has good storage properties.
A composition according to the invention is also cosmetically suitable and does not cause irritation of the scalp even after prolonged contact without rinsing.
An object of the invention, therefore, is to provide a novel alkylpolyglycoside and pyrimidine derivative based composition to induce and stimulate hair growth and/or reduce its loss.
Another object of the invention is to provide pharmaceutical compositions for topical application based on this composition.
A further object of the invention is to provide a cosmetic hair and scalp treatment method using this composition.
Further objects of the invention will become clear from the following description and examples.